the wpath soc is a very accessible document with a very nuanced and careful approach to treatment of adolescents and children, it explicitly deals with the potential fragility of such decisions - and the cases which are very stable early on and benefit from early access, and how to discern them.
they didn't take out the brains or caution. they just took out the inflexible and useless rigid age barriers.
its really worth a read, chapter 6 is the one relevant here